Devices are typically operated by controls. Controls may be physical or non-physical. The location of physical controls may be detected by touch alone. For example, even when in the dark, a user can locate a light switch by feeling the wall around the location in which light switches are typically positioned. Non-physical controls, on the other hand, cannot be detected by touch alone. For example, an icon on a computer screen cannot be detected simply by running one's fingers across the computer screen. In this example, the icon cannot be physically detected because the screen location of the icon feels no different to the touch than the rest of the screen.
Users typically rely on sight to locate non-physical controls. For example, to select an icon that is displayed on a touch screen, a user would typically look at the screen to locate the icon, and then use visual feedback to guide the user's finger to that location.
When users are not able to easily see the non-physical controls of a device, it may become difficult or impossible for them to operate the device. A variety of circumstances may lead to situations in which users are not able to see non-physical controls of a device. For example, some users may be visually impaired. As another example, lighting may be insufficient. As yet another example, some devices may not be able to generate visual depictions of non-physical controls, either because the devices or broken, or because they are not designed with that functionality.
Even when conditions exist that would otherwise allow a user to see a non-physical control, the user may have reasons for not looking at the device. For example, a user that is watching a movie or driving a vehicle may want their vision to remain focused elsewhere, rather than looking for the location of a non-physical control of a device. Similarly, a user may want to operate a device while keeping the device in his or her pocket.
Based on the foregoing, it is clearly desirable to help users operate non-physical controls when the users either cannot or do not want to use their vision to locate the non-physical controls.
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.